A stand-alone power system (SAPS), also known as remote area power supply (RAPS), may be an off-the-grid electricity system that may be suitable for locations that are not fitted with an electricity distribution system. Typical SAPS may include one or more methods of electricity generation, energy storage, and regulation. Storage may be implemented as a battery bank, but other solutions exist including fuel cells and super capacitors, for example. Power drawn directly from the storage may be used for lighting as well as for other direct current (DC) appliances. Stand-alone photovoltaic power systems may be independent of the utility grid and may use solar panels only or may be used in conjunction with a diesel generator, a wind turbine or batteries, for example. Challenges for the design and implementation of stand-alone power systems may include improving their performance, establishing techniques for accurately predicting their output, and reliably integrating them with other generating sources.